Lifting-jack



(No Mbdl.) .v

H. H. GLEVER. LIFTING JACK. No. 402,141. Patented Apr. 30, 1889.

WITNESSES,

N. PETERS. PbmLithbgriphlr, Wndlington. EC.

UNITED STATES PATENT OFFICE.

HENRY ll. CLEVER, OF CLEVERSBURG, PENNSYLVANIA.

LlFTlNG-JAC K.

SPECIFICATION forming part of Letters Patent No. 402,141, dated April 30, 1889.

Application filed Jul 13, 1888. Serial No. 279,892. (No model.)

To all whom it may concern.-

Be it known that I, HENRY H. CLEVER, a

citizen of the United States of America, re-

siding at Cleversburg, in the county of Cumberland and State of Pennsylvania, have invented certain new and useful Improvements in Lifting-Jacks; and I do declare the following to be a full, clear, and exact description of the invention," such as will enable others skilled in the art to which it appertains to make and use the same, reference being had .to the accompanying drawings, and to the letters ,and figures of reference marked thereon, which form a part of this specification.

My invention has relation to lifting-jacks of that class known as lever lifting-jacks.

The object of my invention is to simplify and improve existing constructions in implements or machines of the class; and my invention therefore consists in the novel construction and combination of parts, as will be hereinafter fully explained and described, and especially as is particularly pointed out and distinctly claimed.

I have fully illustrated my improved device in the accompanying drawings, wherein- Figure 1 is a side view, in elevation, of the liftingjack, one side of the casing being moved to show the mechanism. Fig. 2 is a front view of the lifting-rack. Fig. 3 is a detail View of the lever with its pawls. Fig. 4 is a perspective showing the arrangement of the pawllatch for releasing the upper or stop pawl, and Fig. 5 is a detail showingthe spring and pawl to hold the rack in any position of elevation. Fig. 6 is a top view showing the lifting-rack in cross-section and arranged in the casing; andFig. 7 is a front view of the upper part of the jack, showingthe frictionspring and set-screw.

Reference being had to the drawings, A designates the .casin g, which consists of a substantial base-piece, 1, on which are erected or formed three sides of the vertical boxing or casing 2 3 at, one side being left open, and to which is fitted a removable plate, 5. In the top 6 of the casing is formed a slot, 7, formed with a guide-groove, 8, to receive the flange on the lifting-rack. The inner face of the removable plate 5 is cut away, as at 9, to make room for one of the projecting ends of the lever, and in this cut-away part is a pintle, 10,

to serve as a fulcrum for the lever.

B designates the lifting-rack, arranged in the slot in the top of the casing, with its back against the inner face of that side of the easing, and formed with a rack, 11, to engage the gear of the small gear-wheel. At one side of the rack is a flange, 12, which serves to strengthen the teeth of the. rack by connecting them at one end, and also, being disposed in the groove 8 0f the slot, serves as a guide to the rack in its reciprocations. On the top of the rack is fixed a seat, 13, adapted to receive or set under the weight to be lifted.

O designates the gears, which consist of the larger ratchet and lifting wheel 14:, having the square faces of the ratchets upward to engage the stop-pawl suspended in the casing, and extending from and formed at a part thereof is the small gear 15, which engages the rack. The gears have end journalsand are mounted in bearings formed in the casing, substantially as shown. The shaft of the gears is given a limited end-play, in order that the face of the large ratchetrwheel may be moved in frictional contact with the inner face of the easin g, to restrain and ease'the fall of the rack,

' as hereinafter more fully stated.

D designates, the lever, mounted on the pintle 10 on the side of the caseand bearing 16, fixed on the case. The weight end of the lever is formed with an open-end slot, 17, which sets over the ratchet-gear, so as to bring the lifting-pawl of the lever in convenient and certain engagement with the ratchets of the gear. In the under face of the lever is formed a channel, 18, covered by a plate, 19, and in this channel is arranged a spring-actuated bar, 19 having a rod, 20, connected at its outer end to a bell-crank lever, 21, pivotally mounted on the lever-handle in convenient position to be readily manipulated by the hand ,ofthe operator.

To the under face of the top of the casing is pivotally suspended a stop-pawl, 22, arranged to engage the upper faces of the ratchets of the gear and stop the wheel from reversing when the rack is being moved upward with the weight. To make the engagement of this stop-pawl certain, I fix a spring, 23, in the casing and arrange the free end thereof to bear inward on the stop-pawl. As this arrange'ment necessitates the employment of means to disengage the stop-pawl whenever required, I have devised the following combination of elements:

In the removable side of the casing is formed a liorizontally-arrangod slot, 2t, and to the outer face of the side of the casingis pivoted a latch, 25,having its upper end bentat right angles to the body of the latch, as at 26, and the bent part of the latch is projected through the slot 24, with the end in engagement with the inner face of the stop-pawl. To the latch ccured one end of a rod, 27, having its nor ond secured to the arm of a bell-crank ltver, .3 pivotally fulcrumed to .the handle of the lever, substantially as shown.

The casing is formed to embrace and conceal all the mechanism involved, except the love: and its mountings and. the top of the racl-i-bar, and to effect this I form the rear side of the casing with a swell, as at 29, and the opposite side wider at the upper part to make room in both directions for the ratchetwheel. The mechanism is thus shielded from exposure consequent in the common construe tions, and the hands of the person operating the lifting-jack are free from any danger of contact with the gear or engaging end of the lever.

To provide means for restraining the fall of the rack when the pawls are both disengaged, a spring-bar, 30, is secured against the side of the casing. This spring is arched, and has slots 31 in each end, through which the fastening-screws are projected, as shown. In the middle of the spring is a threaded hole, in which is fitted a set-screw, 32, which bears with its end on the end of the shaft or journal of the gears, and when in force pushes the shaft endwise with the face of the ratchet-wheel against the face of the casing, and thus retards or restrains the downward movement of the rack when the pawls are free.

The operation may be stated as follows: To lift a weight, all that is necessary is to bear down on the lever, extending the movement until the limit of its sweep is reached, which action carries the gear around and lifts the rack. As the lever is moved down and the ratchets pass the stop-pawl, that element is thrown wit-h its end over the square face of the ratchets, and will hold the wheels and rack from reversing. The lever is then raised for another bite with the ratchets, and the downward movement repeated when it is desired to lower the rack when a weight is upon it. The lever is borne down to release or relieve the contact of the ratchet and stop-pawl, and then the bell-crank lever, in connection with the latch of the stop-pawl, is borne down until the end of the stop-pawl is drawn free from the edge of the ratchet, when the lever is moved upward, and the rack thus lowered to the extent of the sweep of the lever, the limit of which being reached the bell-crank lever of the stop-pawl is released, the pawl thrown in position over the ratchet-tooth, and the rack thus held. If further downward movement is required, the lifting pawl or bar is drawn back, the lever carried down, and the operation last above specified repeated. If it is desired to lower the rack when no weight is upon it, both pawls are drawn back free from the ratchet-gear, when the rack will run down by gravity, the force of its descent being regulated by means of the friction-spring and set-screw, as specified.

\Vhat I claim is 1. The combination, with the casing A, formed with a slot, 7, in its top 6, to receive the lifting-rack B, said slot having a groove, 8, at its edge, of the lifting-rack B, having the teeth united at the edge bya continuous flange, 12, the gear-wheel mounted in the casing, the stop-pawl 22, depending from the roof of the casing, the lever D, fulcrumed on bearings in the casing and formed with an open-end slot, 17, to set about the ratchet-wheel, and provided with a spring-actuated bar, 19*, a bellcrank lever 21, on the lifting-lever D, to operate the spring-actuated bar 19*, the latch 25, mounted on the casing and arranged with its free end to bear out on the stop-pawl, and a bell-crank lever, 28, mounted on the lifting-lever to operate said latch, substantially as described.

2. In a lifting-jack, the combination, with the reciprocable lifting-rack B, a gear and ratchet wheel, 14, mounted in the casin g, and

a pawl, 22, to hold the gear and ratchet against reversing, of a lifting-lever, D, fulcrumed on bearings in the casing, and formed with an open-end slot, 17, to set about the ratchet wheel, a spring actuated pawl-bar, 19*, mounted on the lifting-lever, and a bellcrank lever, 21, on the lifting-lever to operate the stop-bar.

3. The casing A, having an enlarged upper portion to hold the operating mechanism, the lifting-rack B, arranged in the casing with its rack against the wall thereof, and formed with a side flange, 12, to connect the teeth and guide the bar, combined gear and ratchet wheels 14, mounted on bearings in the casing, a spring-actuated pawl, 22, to stop the gears against reversal, a lever, D, to give intermittent motion to the gear and ratchet, and having a spring-pawl, 19 to engage the ratchets, and two levers, 21 28, mounted on the lifting-lever D to release the pawls of the lever and easing, all substantially as described.

at. In combination with the casing, the reciprocable rack B, and gears, the spring-bar 30, secured to the side of the casing, and the set-screw 32, projected through the springbar with its end to bear on the end of the journal of the gears, substantially as and for the purpose specified.

In testimony whereof I affix my signature in presence of two witnesses.

HENRY ll. CLEVER.

\Vitnesses:

J. ARTHUR SCHLIDETER, J. T. RIPPEv. 

